I have my exact solution u and calculated by the mixed finite element method u_h, and I wonder if given such data and mesh data can help me:

script.m find a matlab command or allow me to calculate the errors, ie the norm of the difference between the exact solution and the approximation using finite element method (mixed) (norm L ^ 2(\Omega), H ^ 1(\Omega) and H (div;\Omega)).


any help or references are welcome.